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    International Conference on Industrial

    Engineering Science and Applications-2014

    Contents Paper ID Title of Papers Page No.

    02 Progressive Failure Analysis of Laminated Composite Shells A Review 001-006

    05 Application of Neural Network for Identification of Cracks on Cantilever Composite

    Beam

    007-011

    06 Dynamic response of a simply supported beam with traversing mass 012-014

    08 Mathematical modeling of steady state temperature distribution due to heat loss

    from weld bead of a square butt joint

    015-020

    10 Computational Analysis of Shell Fluid of Shell and Tube Heat Exchanger Allowing

    the Outcome of Baffles Disposition on Fluid Flow

    021-025

    11 Thermal Analysis of Porous Fin with Internal Heat Generation 026-031

    13 Reliability Analysis of Two Lathe Machines Arranged in a Machining System 032-036

    15 Genetic algorithm based performance analysis of 3-phase self-excited induction

    generator

    037-041

    16 Comparative Study of Machining Processes by Process Capability Indices 042-045

    17 Heat transfer analysis in porous fin of different profiles using Vibrational iteration

    method

    046-051

    19 Patient Information implantation and reclamation from compressed ECG signal by

    LSB watermarking technique

    052-057

    20 Vibration Characteristics of Rotating Simply Supported Shaft in Viscous Fluid 058-063

    21 Diagnosis of Damage in Composite Beam Structures using Artificial Neural

    Network with Experimental Validation

    064-068

    22 Finite Element Analysis of Hip Prosthesis for Identification of Maximum Stressed

    Zone

    069-072

    23 Multi Channel Personal Area Network(MCPAN) Formation and Routing 073-079

    24 Vibration analysis of a cracked Timoshenko beam 080-084

    25 Silicon on Insulator based Directional, Cross Gap and Multimode Interference

    Optical Coupler design

    085-090

    26 An Analysis of Short Term Hydrothermal Scheduling using Different Algorithms 091-096

    28 Monitoring of the lung fluid movement and estimation of lung area using Electrical

    Impedance Tomography: A Simulation Study

    097-100

    30 Multi-objective design of realistic load frequency control system using particle

    swarm optimization

    101-105

    31 Hybridizing DE with PSO for Constrained Engineering Design Problems 106-111

    33 Harmonic Distortion Optimization of Generalized A-Symmetrical Series/Parallel Multilevel Converter with Fewer Switches

    112-117

    34 Detailed study and proposed restoration of damaged structural bracket supports for

    three tier insulated piping system by using anchoring methodology in filter house

    structure of solvent dewaxing unit

    118-122

    39 Design and Development of a Heating- Cooling Belt using Thermoelectric

    Refrigeration for Medical Purposes

    123-127

    42 Power line filter design considering losses and parasitic characteristics of passive

    lumped components

    128-133

    43 CFD analysis of cambered airfoil for H-rotor VAWT 134-138

  • ix

    International Conference on Industrial

    Engineering Science and Applications-2014

    45 Modeling of active transformation of microstructure of two-phase Ti alloys during

    hot working

    139-144

    47 Value Based Planning of Renewable DGs in Distribution Network Incorporating

    Variable Power Load Model and Load Growth

    145-150

    49 Phase Angle Measurement using PIC Microcontroller with Higher Accuracy 151-154

    50 Automatic Electronic Water Level Management System using PIC Microcontroller 155-158

    55 Effect of Temperature on Photovoltaic Cell performance 159-161

    57 Optimum Process Scheduling Using Genetic Algorithm in an Existing Machine

    Layout

    162-166

    59 A review parametric performance of solar still 167-172

    61 Differential Difference Current Conveyor (DDCC) Based Current mode Integrator

    and Differentiator

    173-176

    62 Performance analysis of 2 stroke gasoline engine by using compressed air 178-181

    63 Design of Wide Band Digital Integrator and Differentiator 182-185

    66 Tracking Mobile Targets Through Wireless HART 186-190

    67 Hysteresis Compensation using Modified Internal Model Control for Precise Nano

    Positioning

    191-196

    68 Reversible Data Hiding using Wavelet Transform and Compounding for DICOM

    Image

    197-201

    69 Study on Photovoltaic System for Isolated and Non-Isolated Source Cascaded Two

    Level Inverter (CTLI)

    202-206

    70 Mass Measuring System Using Delay-and-Add Direct Sequence (DADS) Spread

    Spectrum Method

    207-210

    71 Fault analysis of wind generator connected power system using differential equation

    technique

    211-215

    72 Biomedical application using zigbee 216-218

    73 Resonant Frequency of 300-600-900 Right Angle Triangular Patch Antenna with

    and without Suspended Substrate

    219-222

    74 Model Free Adaptive Control in Industrial Process: An Overview 223-226

    76 Simulation of IGBT fed Mirror Inverter based H.F. Induction Cooker 227-230

    82 A Hybrid Intelligent Algorithm Applied in Economic Emission Load Dispatch

    Problems

    231-235

    86 Performance assessment of power system by incorporating Distributed generation

    and Static VAR compensator

    236-241

    87 A study of Performance Analysis on Multi-bus Power Grid Network Modeling 242-246

    89 Reliability Assessment of Energy Monitoring Service for a Futuristic Smart City 247-252

    92 Performance Characteristics of 2x50kwp Roof top PV Power Plant System 253-257

    93 Multiple Distributed Generator allocation by modified novel power loss sensitivity

    for loss reduction

    258-262

    94 A Novel Constraint Increasing Approach for solving Sudoku puzzle 263-267

    97 Kinematic synthesis of six bar gear mechanism 268-272

    98 A Simulation Based Geometrical Analysis Of MEMS Capacitive Pressure Sensors

    for High Absolute Pressure Measurement

    273-277

    100 RAHSIS: A Tool for Reliability Analysis of Hardware Software Integrated Systems 278-283

    101 Steel Fiber Reinforced Concrete in the service of Civil Engineering 284-289

    102 Optimal Control of singular systems via Haar function 290-293

  • x

    International Conference on Industrial

    Engineering Science and Applications-2014

    103 Baseline Wander and Power Line Interference Removal in ECG Signal 294-297

    105 Prediction of relative density of clean sand: A support vector machine approach 298-301

    107 Strengthening of Structures using Glass Fibre Reinforced Plastic 302-306

    109 Removal of sodium do-decylsulfate from waste water using adsoption on citrus

    lemettioides

    307-310

    110 Design of Adiabatic Adder Structures for Low Power VLSI & DSP Applications 311-314

    114 Variable Frequency Drives - a successful mode of speed control of AC motors 315-319

    115 Using Appointment system to improve the loading process of trucks in a steel plant:

    A simulation based case study

    320-324

    116 Productivity Improvement Through Line Balancing using Simulation 325-329

    117 A Genetic Algorithm Trained Artificial Neural Network Based Selective Harmonic

    Elimination Technique for Cascade Multilevel Inverters

    330-335

    118 Performance Analysis of Genetic Algorithm in Direction of Arrival of Wideband

    Sources Over Wide SNR Range

    336-339

    119 Intelligent Co-ordinated Control for Boiler Turbine Unit 340-343

    120 Vulnerability Assessment of Reinforced Concrete Buildings having Plan Irregularity

    using Pushover Analysis

    344-348

    123 A comparative analysis of performance of three phase four wire DSTATCOM

    topologies for power quality improvement

    349-352

    126 How Ergonomics play an important role in productivity improvement of an

    organization

    353-358

    127 Modeling and Simulation of YNVD Transformer for Single Phase Electrified

    Traction System

    359-362

    128 Transient Response and Load Sharing Improvement in Islanded Microgrids 363-367

    129 Intelligent Hybrid Fuzzy PD Control for Trajactory Tracking of Robot Manipulator

    and Comparative Analysis

    368-372

    130 Improvement in DC- link Voltage of Doubly Fed Induction Generator using SMES 373-377

    131 Implementation of energy storage and FACT device with renewable power

    generation system

    378-381

    132 Flexible pavement cost modeling for weak subgrade stabilized with fly ash and lime 382-386

    133 Prediction of compression index of clay using artificial neural network 387-390

    134 On the Directivity and Multiband Characteristics of Sierpinski Fractal on Bowtie 391-396

    136 Power Quality Improvement Using DPFC Under Fault Conditions 397-401

    137 Benchmarking and Analysis of the User-Perceived Performance of EPICS based

    ICRH DAC

    402-405

    140 Power Flow Control in Smart Micro Grid using Fuzzy Controllers 406-409

    144 Harmonics Mitigation with the help of Zsource Inverter based DVR 410-414

    146 Assessment of Retailers quality in Dairy Supply Chain Using AHP Technique 415-419

    149 Effect of Conflicting Vehicles on Service Delay Under Mixed Traffic Conditions 420-425

    150 Defining Level of Service at Uncontrolled Median Openings through K-Medoid

    Clustering

    426-432

    159 Optimum Design of FRP Rib Core Bridge Deck Panel using Gradient based

    Optimization

    433-439

    160 Optimization design of FRP web core skew bridge deck system using Genetic

    Algorithm

    440-446

  • Progressive Failure Analysis of Laminated

    Composite Shells A Review

    Jayashree Sengupta

    Post-Graduate Student: Department of Civil

    Engineering

    Jadavpur University

    Kolkata, India

    [email protected]

    Dipankar Chakravorty

    Professor: Department of Civil Engineering

    Jadavpur University

    Kolkata, India

    [email protected]

    [email protected]

    AbstractComposite materials present striking potentials to

    be tailored for advanced engineering applications. Thin walled

    composite panels are one of the most utilized structural elements

    in construction. The increasing use of the composites necessitates

    for the precise and viable methods of analysis- the life prediction

    being an important issue. The initiation and propagation of

    failure until final fracture of the structure assesses the life of the

    structure. Unnoticed internal failures may lead to fatal collapse,

    thus making first ply and progressive failure of much concern to

    researchers. This paper addresses the various literatures that

    have been published so far associated with the progressive failure

    of the composite laminated shells; also it reflects the five failure

    theories working behind.

    Keywordsprogressive failure; laminated composites; plates; shells; first-ply failure; literature review.

    I. INTRODUCTION

    Over the last few decades, composite laminates are

    exceedingly used in various engineering sectors like

    construction, mechanical, aerospace and marine; their

    advantages being their high strength and stiffness to weight

    ratio, extended fatigue life and various other superior material

    properties. Unlike isotropic materials, the composites bear a

    complex response to loadings which can be analysed now by

    FEM.

    The failure mechanisms are best understood at micro level.

    However on a macroscopic level, the failure analysis is more

    intricate. Upon the application of loads, the laminate

    undergoes stresses closely related to the properties of the

    constituent phases, i.e., matrix, fibre, and interface-interphase.

    The first ply failure occurs when stresses in the weakest

    lamina exceed the allowable strength of the same changing the

    material properties. For a composite construction it is thus

    crucial to locate this change. A composite material undergoes

    transition in multiple phases. At first-ply failure, redistribution

    of stresses occurs within the remaining laminae of the

    laminate. This does not necessarily mean that the whole of

    lamina has undergone failure; it only indicates the initiation.

    The laminate will be termed as damaged with degraded

    properties. The constitutive relations are changed followed by

    reduction in stiffness. The stiffness of the failed lamina is not

    taken into account and the rest are considered to remain

    unaffected. The remaining laminae continue to take up load

    till the ultimate strength is reached. A ply-by-ply progressive

    analysis and the damage so done is analysed by the inclusion

    of different failure criteria which allows for the identification

    of the location of the failure.

    II. LITERATURE REVIEW

    Tsai and Wu [1] were the first to present that an

    operationally simple strength criterion cannot possibly explain

    the actual mechanisms of failures. Failures are but a multitude

    of independent and interacting mechanisms. They made use of

    strength tensors fulfilling the invariant requirements of

    coordinate transformation; interaction terms were treated as

    independent components and the difference in strengths owing

    to positive and negative stresses were accounted for making it

    way too improved than the Hill criterion wherein the

    interactions were not independent of each other. Previously,

    most initial failure analyses was concerned with the in-plane

    loading cases, perhaps because of being more governing in

    laminated structural elements. But Turvey [2] focused his

    study where flexural load dominated limiting his research to

    high modulus GFRP and CFRP and cross-ply symmetric

    configurations. He considered Tsai-Hill failure criterion as it

    is in good correlation for the GFRP laminates; expressed both

    the deflection surface and lateral pressure deflection in Navier

    double series form. Though his research was unrestricted on

    grounds of loading, he however chose three cases viz.

    uniformly distributed load, patch loading and hydrostatic

    loading varying linearly.

    Reddy and Pandey [3] studied the first ply failure for the

    laminated composite plates, subjected to in-plane and/or

    transverse loading, the first order shear deformation theory

    and a tensor polynomial failure criterion (emphasis was laid

    on maximum stress, maximum strain, Tsai-Hill, Tsai-Wu and

    Hoffmans criteria) to predict failure at elemental Gauss points. They inferred that when the laminate was subjected to

    in-plane loading all the failure criteria were capable of

    predicting failure. However when the same was subjected to

    transverse loading, maximum strain and Tsai-Hill happened to

    have different results. The procedure that they depicted was an

    iterative one; once the first-ply failure had occurred the load

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  • was reduced by 20% and the process went on till the

    difference between any two successive failure loads was less

    than 1%. They extended their research on post first ply failure

    emphasizing on the progressive analysis [4]. Tolson and

    Zabaras [5] studied progressive failure in laminated composite

    plates implementing seven degrees of freedom (three

    displacements, two rotations of normal about the plate mid-

    plane, and two warps of the normal). The in-plane stresses

    were calculated from the constitutive equations, but the

    transverse stresses were assessed from the three-dimensional

    equilibrium equations. The normal stress distributions were

    calculated at each Gauss points. Thereafter the stresses were

    employed in five failure criteria (maximum stress, Lee,

    Hashin, Hoffman, and Tsai-Wu) and were checked against

    whether failure had occurred or not. The Lee criterion gave

    the best results.

    Prior to this, Engblom and Ochoa [6] carried out PFA till

    last ply failure; stiffness decrement and damage growth

    followed standard laminate analysis. Analysis was carried out

    on a plate subjected to uniaxial tension and four-point

    bending. Chang and Chang [7] developed the progressive

    damage analysis of notched laminated composites subjected to

    tensile loading. The progressive failure method used a

    nonlinear FEA using the modified Newton-Raphson iteration

    scheme to work out the state of stress in a composite plate.

    Chang and Lessard [8] studied the damage in laminated

    composites containing an open hole subjected to compressive

    loading, wherein the in-plane response of the laminates from

    initial loading to final collapse was studied. A geometrically

    non-linear formulation based on finite deformation theory was

    used. Reddy and Reddy [9] computed linear and non-linear

    first-ply failure loads of composite plates for different load

    cases and edge conditions. The linear loads results varied by a

    maximum of 35% and for non-linear loads it was 50%.

    Besides, this difference was much large for thin laminates

    subjected to transverse loading and quite small for thick

    laminates subjected to in-plane loadings. They extended their

    work [10] to nonlinear progressive analysis using the

    Generalized Laminate Plate Theory (GLPT) of Reddy

    applying a new stiffness reduction format.

    Kim and Hong [11] studied macroscopic failure models

    evaluating the stiffness changes employing shear lag factor

    and fiber bundle failure. Tan and Perez [12] studied

    progressive failure of laminated composites with holes,

    subjected to compressive loading predicting the extent of

    damage at any level of loading. Results showed good

    assessment with the experimental results. Tan [13] had

    previously developed progressive failure model of laminated

    composites subjected to in-plane loading considering the

    environmental impacts (thermal and hygroscopic stresses).

    Kam and Sher [14] studied progressive failure of centrally

    loaded laminated composite plates. The Ritz method, with

    geometric non-linearity, in the Von Karman sense, was used

    to construct the load displacement behaviour. Cheung et al.

    [15] presented a PFA of composite plates by the finite strip

    method based on higher order shear deformation theory and

    Lees failure criterion. Sahid and Chang [16] developed a model for predicting the effects of matrix crack induced

    accumulated damage on the in-plane response of laminated

    composites under tensile and shear loads. Echaabi et al. [17]

    presented a theoretical and experimental study of damage

    progression and failure modes of composite laminates under

    three point bending.

    Kim et al. [18] carried out PFA to predict the failure

    strengths and failure modes (tension, shear-out and bearing)

    which were judged against experimental data, of pin-loaded

    laminated composite plates using the penalty finite element

    method. Hashins failure criteria was performed for damage evaluation in the laminates. Gummadi and Palazotto [19]

    performed PFA of composite cylindrical shells with large

    rotations based on Langrangian approach and the due changes

    in the constitutive relations were discussed; considered failure

    modes of matrix cracking, fiber breakage and delamination;

    damage progression followed maximum stress criterion. The

    stiffness matrix was determined based on Greens strain and 2nd Piola Kirchoff stresses. Greens strain was transformed to Almansi strain which was further transformed into material

    axis system and was used to determine the Euler stresses.

    These Euler stresses were the key to failure determination.

    Padhi et al. [20] presented their detailed study on progressive

    failure and ultimate collapse of laminated composites using

    Hashin and Tsai-Wus failure criteria. They made use of Newton-Raphson Method with a force and moment residual

    convergence of 0.5% and displacement correction

    convergence of 1%. The model was capable of assessing type

    and extent of damage all throughout.

    Spottswood and Palazotto [21] determined the response

    together with material failure of a thin curved composite shell

    resisting transverse loading, incorporated simplified large

    displacement/rotation (SLR) theory and compared the results

    with previously published available data; failure criteria being

    Hashins. Pal and Ray [22] carried out PFA under transverse static loading in linear elastic range distinctively for both

    antisymmetric and symmetric angle ply laminates. Knight Jr.

    et al. [23] reviewed the overall computational issues and

    requirements for performing PFAs using STAGS (Structural

    Analysis of General Shells) for solving non-linear quasi-static

    structural response problems including special details. Prusty

    [24] studied unstiffened and stiffened composite panels under

    transverse static loadings in the linear elastic range. Eight-

    noded isoparametric quadratic elements with three-noded

    curved beam elements were modeled and checked against

    various failure theories. Ultimate ply failure loads for the

    stiffened panels with cross-ply and angle-ply laminations in

    the shell was analyzed.

    Akhras and Li [25] proposed a spline finite strip method

    PFA of thick composite plates based on Chos higher order zigzag laminate theory and Lees failure criterion. The transverse shear stresses were obtained directly from the

    constitutive equations; the shear correction factor was not

    required as for the first-order shear theory. The procedure

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  • involved an incremental load analysis through modified

    Newton-Raphson method and standard PFA method showing

    good agreement with the 3D finite element solutions. Las and

    Zemck [26] proposed a PFA model of unidirectional

    composite panels using Pucks fiber and inter-fiber criteria demonstrating the results with examples of tensile tests of

    single-ply panels. Tapered laminated plates under the action of

    uniaxial compression were investigated by Ganesan and Liu

    [27] predicting different failure loads and the associated

    displacements, locations and modes. The influences of the

    tapered configuration, lay-up configuration, and fiber

    orientation were also the concern of the study. Earlier,

    Ganesan and Zhang [28] had conducted a detailed

    investigation of the progressive failure of uniform thickness

    laminates subjected to uniaxial compression. Singh et al. [29,

    30, 31] also studied the progressive failure of uniform

    thickness plates subjected to different loads. Progressive

    damage analysis methodology for stress analysis of composite

    laminated shells using finite strip methods based on Mindlins plate-bending theory were addressed by Zahari and El-Zafrany

    [32], where the non-linear equations were derived using the

    tangential stiffness matrix approach; validation was done by

    comparing the results with analysis in ABAQUS.

    Sandwich composite panels under quasi-static impact were

    investigated by Fan et al. [33]. Hashins and Besants criteria were checked for different failure mechanisms. Ply

    discounting method was employed as the strategy for material

    degradation. Ahmed and Sluys [34] designed a computational

    model presenting a mesoscopic failure model studying matrix

    cracking, delamination and the combined effect. A mesh

    independent matrix cracking was modeled with discontinuous

    solid-like shell element (DSLS); delamination was presented

    by a shell interface model. Besides material nonlinearities, the

    numerical model simulated geometrical nonlinearities.

    Anyfantis and Tsouvalis [35] studied post-buckling

    progressive and final failure response of stiffened composite

    panels using ANSYS. The intralaminar, fiber and matrix

    failure modes in compression and tension were addressed

    using a combined framework of Hashins and Tai-Wu failure. The PFA method included intralaminar failures that

    stimulated material degradation of the failed layers.

    Pietropaoli [36] too worked on progressive failure of

    composite structures using a constitutive model implemented

    in ANSYS. Standard ply discount technique was used and the

    onset and progression of damage was observed and the results

    were validated against experimental results. Bogetti et al. [37]

    studied the nonlinear response and progressive failure of

    composite laminates under tri-axial loading. A program was

    build and executed in MATLAB; this analyzed and displayed

    the failure envelope. Philippidis and Antoniou [38] computed

    a PFA model for glass/epoxy composite giving an extensive

    comparison between numerically calculated stressstrain response up to failure and experimental data. Crdenas et al.

    [39] presented a reduced-order FE model suitable for PFA of

    composite structures under dynamic aeroelastic conditions

    based on a Thin-Walled Beam theory predicting both onset

    and propagation of damage.

    III. FAILURE CRITERIA

    A. Notations

    FX Overall Longitudinal Strength

    FY Overall Transverse Strength

    FXT , FYT Tensile strength in X and Y direction

    respectively

    FXC , FYC Compressive strength in X and Y direction

    respectively

    FS In-Plane shear strength

    , Normal stresses in X and Y direction

    respectively

    Shear stress in X-Y plane

    , Strain along X and Y direction respectively

    Shear strain

    ,

    Ultimate Strain along X and Y direction

    respectively

    Ultimate Shear strain

    Generally failure criteria can be either non-interactive

    (independent) or interactive (polynomial). An independent

    criterion gives the mode of failure, be it longitudinal or

    transverse, tensile or compressive or shear mode, and is

    simple to apply. However, the effect of stress interactions is

    ignored. The stress interactions are addressed by the

    polynomial failure criteria; but in this case, the failure mode is

    disregarded. The laminate may indicate failure using a non-

    interactive theory. If not so, the lamina should be checked

    using the interactive failure. It may so happen that the

    independent stresses do not initiate failure but their

    interactions may. Hence it is best to check for failure through

    both independent and non-interactive criteria.

    B. Independent Failure Criteria

    1) Maximum Stress Criteria: According to maximum stress theory, the failure initiates if at least one of the criteria

    is satisfied,

    1,

    1,

    1 (1)

    2) Maximum Strain Criteria: According to maximum strain criteria failure occurs if any of the following is reached,

    1,

    1,

    1 (2)

    C. Interactive Failure Criteria

    Failure can be predicted by the following tensorial form,

    1 (3)

    which when expanded in two dimensional form gives,

    1

    (4)

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  • The failure indices for different theories are as follows.

    TABLE I. FAILURE INDICES

    Failure

    Indices

    Tsai

    Hill(a) Tsai Wu Hoffmann

    (a). If > 0, = FXT else = FXC . Similarly if > 0, = FYT else = FYC

    IV. PROGRESSIVE FAILURE ANALYSIS

    To carry out PFA, it is necessary to determine the first ply

    failure of the laminate. The material properties of the lamina,

    mechanical loading i.e. forces and moments, and layer

    orientation are read. Based on the inputs, the stresses at each

    Gauss point within individual lamina were evaluated and are

    verified with the failure criteria to check any possible failure.

    If any failure had occurred, the material properties at that

    point were modified with accordance to the observed failure

    mode, and the stresses were recalculated at FPF load, using a

    property degradation technique- (A) Total-Ply Failure Method

    and (B) Partial-Ply Failure Method. Thereafter, a check is

    performed to see whether the second ply fails at FPF load, if

    not, a load increment is performed and with the reduced

    stiffness the process continues till the ultimate failure load

    occurs and at that stage convergence of stresses cannot be

    achieved numerically . A typical PFA is demonstrated in Fig.

    1.

    A. Total Ply Failure Method

    On reaching the failure, the strength and stiffness of the

    failed ply is totally reduced to zero. This implies that if the ply

    undergoes matrix failure, it is no longer able to carry load in

    fibre direction, which, may not be the case. Thus this method

    somehow underestimates the laminate strength.

    B. Partial Ply Failure Method

    In this approach, the failure mode is taken into account. If

    the ply fails due to fibre failure, the stiffness of the failed ply

    is reduced to zero. However, if it is a matrix controlled failure

    or shear failure, the longitudinal modulus retains its value but

    the transverse and shear modulus are set to zero.

    Fig. 1. Flowchart of Progressive Failure Analysis Methodology

    V. CONCLUSION

    Various literatures on laminated composite structures and are

    studied in this paper. It is visibly evident that prediction of the

    failure process, the initiation and growth of the damages, and

    the maximum loads that the structures can withstand before

    failure occurs is essential for assessing the performance of

    composite laminated plates and for developing reliable and

    safe design. It is found that such studies on beams and plates

    have appeared in quite a number of places although similar

    studies on composite shells are really scarce. Hence failure

    analyses of composite shells need careful attention.

    Cylindrical and spherical shells enjoyed quite an importance;

    however their evaluation on progressive failure is still an area

    of interest. Industrial shell forms like conoids and skewed

    hypar need attention as well. These shells are ruled, doubly

    curved, aesthetically appealing and easy to cast and fabricate. Hypar shell has wide applications in engineering and was studied

    by a number of researchers like Kielb et al. [40], Seshu and

    Ramamurti [41] and Qatu and Leissa [42]. Researchers like Das

    and Chakravorty [43-46, 48] and Kumari and Chakravorty [48,

    49] also studied behavioral characteristics of laminated conoidal

    shells. These shell forms are to be studied for failure also.

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  • REFERENCES

    [1] S. W. Tsai and E. M. Wu, A General Theory of Strength for Anisotropic Materials, Journal of Composite Materials, Vol. 5. 1971, pp. 58-79.

    [2] G.V.Turvey, An initial flexural failure analysis of symmetrically laminated cross-ply rectangular plates, International Journal of Solids Structures, Vol. 16, 1980, pp. 451-463.

    [3] J.N. Reddy and A.K. Pandey A first ply failure analysis of composite laminates, Computers and Structures, Vol. 25. No. 3, 1987, pp. 371-393.

    [4] A. K. Pandey and J. N. Reddy A Post First-Ply Failure Analysis of Composite Laminates AIAA Paper 87-0898, Proceedings of the

    AIAA/ASME/ASCE/AHS/ASC 28th Structures, Structural Dynamics, and

    Materials Conference, 1987, pp. 788-797.

    [5] S. Tolson and N. Zabaras, Finite element analysis of progressive failure in laminated composite plates, Computers and Structures, Vol.38, 1991, pp. 361376.

    [6] O. O. Ochoa and J. J. Engblom Analysis of Failure in Composites. Composites Science and Technology, Vol. 28, 1987, pp. 87-102.

    [7] F. K. Chang and K. Y. Chang, A progressive damage model for laminated composites containing stress concentrations., Journal of Composite Materials, Vol.21, 1987, pp. 834-855.

    [8] F. K. Chang and L. B. Lessard, Damage tolerance of laminated composites containing an open hole and subjected to compressive loadings: Part I.

    Analysis, Journal of Composite Materials, Vol.25, 1991, pp. 2-43.

    [9] Y. N. S. Reddy and J.N. Reddy, Linear and non linear failure analysis of composite laminates with transverse shear, Composite Science and Technology, Vol. 44, 1992, pp. 227-255

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    epoxy composites in flexural bending test. Journal of Reinforced Plastics and Composites Vol. 15, 1996, pp.740-755.

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    [23] Norman F. Knight Jr., Charles C. Rankin, Frank A. Brogan, STAGS computational procedure for progressive failure analysis of laminated

    composite structures, International Journal of Non-Linear Mechanics Vol.37,

    2002, pp. 833849

    [24] B. Gangadhara Prusty, Progressive Failure Analysis of Laminated Unstiffened and Stiffened Composite Panels, Journal Of Reinforced Plastics And Composites, Vol. 24, No. 6, 2005 pp.633-642.

    [25] G. Akhras and W.C. Li Progressive failure analysis of thick composite plates using the spline finite strip method, Composite Structures Vol.79, 2007, pp.34-43

    [26] Vladislav Las and Robert Zemck , Progressive Damage of Unidirectional Composite Panels, Journal of Composite Materials, Vol. 42, No. 1, 2008 pp. 25-44

    [27] Rajamohan Ganesan and Dai Ying Liu, Progressive failure and post-buckling response of taperedcomposite plates under uni-axial compression, Composite Structures, Vol.82, 2008, pp. 159176

    [28] R. Ganesan and D.Zhang, Progressive failure analysis of composite laminates subjected to in-plane compressive and shear loadings, Science and Engineering of Composite Materials, 2004, Vol.11 (23), pp. 79-102.

    [29] SB Singh, A Kumar and NGR Iyengar, Progressive failure of symmetrically laminated plates under uni-axial compression. Structural Engineering and Mechanics 1997, Vol.5, pp. 433-50.

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    [32] R. Zahari and A. El-Zafrany, Progressive failure analysis of composite laminated stiffened plates using the finite strip method, Composite Structures Vol.87, 2009, pp. 6370.

    [33] X.L. Fan, T.J. Wang and Q. Sun Damage evolution of sandwich composite structure using a progressive failure analysis methodology, Procedia Engineering, Vol.10, 2011, pp. 530535.

    [34] A. Ahmed and L. J. Sluys, A Computational Model For Prediction Of Progressive Damage In Laminated Composites, ECCM15 - 15th European Conference on Composite Materials, Venice, Italy, 24-28 June 2012.

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    [36] Elisa Pietropaoli, Progressive Failure Analysis of Composite Structures Using a Constitutive Material Model (USERMAT) Developed and

    Implemented in ANSYS, Applied Composite Materials, June 2012, Vol. 19, Issue 3-4, pp. 657-668.

    [37] Travis A. Bogetti, Jeffrey Staniszewski, Bruce P Burns, Christopher PR Hoppel Christopher PR, John W Gillespie Jr. and John Tierney, Predicting

    the nonlinear response and progressive failure of composite laminatesunder

    tri-axial loading., Journal of Composite Materials, Vol.46, Issue-19-20, 2012, pp. 24432459.

    [38] Theodore P Philippidis and Alexandros E Antoniou , A progressive damage FEA model for glass/epoxy shell structures, Journal of Composite Materials, Vol.47(5), 2012, pp. 623637.

    [39] Diego Cardenas, Hugo Elizalde, Piergiovanni Marzocca, Frank Abdi, Levon Minnetyan, Oliver Probst, Progressive failure analysis of thin-walled composite structures, Composite Structure, Vol.95, 2013, pp. 5362.

    [40] R.E. Kielb, A.W. Leissa and J.C. Macbain, Vibration of twisted cantilever plates a comparison of theoretical results, International Journal of Numerical Methods in Engineering, Vol. 21, 1985, pp. 1365 - 1380.

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  • [43] H. S. Das and D. Chakravorty, Design aids and selection guidelines for composite conoidal shell roofs A finite element application, Journal of Reinforced Plastics and Composites, Vol. 26, No. 17, 2007 pp. 1793-1819.

    [44] H. S. Das and D. Chakravorty, Natural frequencies and mode shapes of composite conoids with complicated boundary conditions, Journal of Reinforced Plastics and Composites, Vol. 27, No. 13, 2008 pp. 1397-1415.

    [45] H. S. Das and D. Chakravorty, Composite full conoidal shell roofs under free vibration, Advances in Vibration Engineering, Vol. 8, No. 4, 2009, pp. 303 310.

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    guidelines, The Journal of Strain Analysis for Engineering Design, Vol. 45, No. 3, 2010, pp. 165 177.

    [47] S. Kumari and D.Chakravorty, On the bending characteristics of damaged composite conoidal shells a finite element approach, Journal of Reinforced Plastics and Composites, Vol. 29, No. 21, 2010, pp. 3287-3296.

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    [50] Mechanics of Composite Materials and Structures by Madhujit Mukhopadhyay, University Press.

    [51] Engineering Mechanics of Composite Materials by Isaac M. Daniel and Ori Ishai, Oxford University Press.

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  • Application of Neural Network for Identification of Cracks on Cantilever

    Composite Beam

    Irshad A Khan

    Mechanical Engg. Department

    National Institute of Technology

    Rourkela, India

    [email protected]

    Adik Yadao

    Mechanical Engg. Department

    National Institute of Technology

    Rourkela, India

    [email protected]

    Dayal R Parhi

    Mechanical Engg. Department

    National Institute of Technology

    Rourkela, India

    [email protected]

    Abstract In the current analysis numerical and neural network methods are adopted for detection of crack in a

    cantilever composite beam structure containing non propagating

    transverse cracks. The presence of cracks a severe threat to the

    performance of structures and it affects the vibration signatures

    (Natural frequencies and mode shapes). The material used in this

    analysis is glass-epoxy laminated composite. The numerical

    analysis is performed by using commercially available software

    package ANSYS to catch the relation between the change in

    natural frequencies and mode shapes for the cracked and un-

    cracked cantilever composite beam. Which subsequently used to

    the design of smart system based on neural network for

    prediction of crack depths and locations following inverse

    techniques. The neural controller is developed with relative

    natural frequencies and relative mode shapes difference as input

    parameters to calculate the deviation in the vibration parameters

    for the cracked dynamic structure. The output from the neural

    controller is relative crack depth and relative crack location.

    Results from numerical analysis are compared with experimental

    results having good agreement to the results predicted by the

    neural controller.

    Keywords Crack; neural network; Natural frequencies; Mode shapes; Ansys.

    I. INTRODUCTION

    Health monitoring and the analysis of damage in the form of

    crack in Beam like dynamic structures are important not only

    for leading safe operation but also retraining system

    performance. Since long efforts are on their way to find a

    realistic solution for crack detection in beam structures in this

    regard many approaches have so far being taken place. When

    a structure suffers from damages, its dynamic properties can

    change. Crack damage leads to reduction in stiffness also with

    an inherent reduction in natural frequency and increase in

    modal damping.

    Discrete Wavelet Transform based method is presented for the

    identification of multiple cracks in polymeric laminate

    composite beam by Andrzej K., [1]. The valuation of the crack

    locations is based on the estimation of natural mode shapes of

    crack and uncrack beams. The mode shapes were estimated

    experimentally using laser Doppler vibrometry. Krawczuk M,

    et al. [2] proposed two models witch gives valuable

    information about the location and size of defects in the

    beams. This method makes it possible to construct beam finite

    elements with various types of cracks (double edge, internal,

    etc.) If the stress intensity factors for a given type of crack are

    known. Damage identification on a composite cantilever beam

    through vibration analysis using finite element analysis

    software package ANSYS is established by Ramanamurthy et

    al. [3]. Damage Algorithm and Damage index method used to

    identify and locate the damage in the composite beam. A

    composite matrix cracking model is implemented in a thin-

    walled hollow circular cantilever beam using an effective

    stiffness approach by Pawar et al. [4]. The composite beam

    model is used to develop a genetic fuzzy system to detect and

    locate the presence of matrix cracks in the structure.

    Continuous wavelet transform is used to identification of

    crack in beam like structures by analysing the natural

    frequency and mode shape of cracked cantilever beam by Rao

    et al. [5]. The effects of cracks on the dynamic characteristics

    of a cantilever composite beam are studied by Kisa M. [6].

    The material of composite beam is graphite fibre-reinforced

    polyamide containing multiple transverse cracks. The effects

    of the crack location and depth and the fibre volume fraction

    and orientation of the fibre on the natural frequencies and

    mode shapes of the beam are explored. Two Damage

    identification algorithms are established for assessment of

    damage using modal test data which are similar in concept to

    the subspace rotation algorithm or best feasible modal analysis

    method by Hu et al. [7]. Moreover, a quadratic programming

    model is set up the two methodologies to damage assessments.

    II. NUMERICAL ANALYSIS

    The numerical analysis is brought out for the cracked

    cantilever composite beam shown in fig1, to locate the mode

    shape of transverse vibration at different crack depth and crack

    location. The cracked beams of the current research have the

    following dimensions.

    Length of the Beam (L) = 800mm, Width of the beam (W) =

    50mm, Thickness of the Beam (H) = 6mm

    Relative crack depth (1=a1/H) varies from 0.0833 to 0.5;

    Relative crack depth (2=a2/H) varies from 0.0.833 to 0.5;

    Relative crack location (1=L1/L) varies from 0.625 to 0.875;

    Relative crack location (2=L2/L) varies from 0.125 to 0.9375;

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  • Properties of Glass-Epoxy composite material in analysis:

    Youngs modulus of fiber = Ef = 72.4 GPa; Youngs modulus

    of matrix = Em = 3.45 GPa;

    Modulus of rigidity of fiber = Gf = 29.67 GPa; Modulus of

    rigidity of matrix = Gm = 1.277 GPa;

    Poissons ratio = f = 0.22; Poissons ratio = m = 0.35;

    Density of fiber = f = 2.6 gr/cm3; Density of matrix = m =

    0.33 gr/cm3;

    Numerical modal analysis based on the finite element

    modeling is performed for studying the dynamic response of a

    dynamic structure. The natural frequencies and mode shapes

    are significant parameters in designing a structure under

    dynamic loading conditions. The numerical analysis is

    accepted by using the finite element software ANSYS in the

    frequency domain and obtain natural frequencies, and mode

    shapes.

    A higher order 3-D, 8 node element having three degrees of

    freedom at each node: translations in the nodal x, y, and z

    directions (Specified as SOLSH190 in ANSYS) was selected

    and used throughout the analysis. Each node has three degrees

    of freedom, making a total twenty four degrees of freedom per

    element. The layers stacking in ANSYS shown in fig2. The

    results of the numerical analysis for the first three mode

    shapes for un-cracked and cracked beam, having cracks

    orientation 1=0.166, 2=0.333 and 1=0.25, 2=0.5 are shown

    in the fig3.

    Fig.2 Layers Stacking in ANSYS

    Fig. 1 Geometry Cantilever beam with multiple cracks

    Fig.3a. Relative Amplitude vs. Relative crack location from

    fixed end (1st mode of vibration)

    Fig.3c. Relative Amplitude vs. Relative crack location from

    fixed end (3st mode of vibration)

    Fig.3b. Relative Amplitude vs. Relative crack location from

    fixed end (2st mode of vibration)

    W

    H

    a2 L1

    L2

    L

    a1

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  • III. NEURAL NETWORK ANALYSIS

    A back-propagation neural controller has been developed for

    detection of the relative crack locations and relative crack

    depth having six input parameters and two output parameters

    as shown in fig. 4. The term used for the inputs are as follows;

    Relative first natural frequency = rfnf; Relative second

    natural frequency = rsnf; Relative third natural frequency =

    rtnf; Relative first mode shape difference = rfmd; Relative

    second mode shape difference = rsmd; Relative third mode

    shape difference = rtmd. The term used for the outputs are as

    follows; Relative first crack location = rcl1 Relative second

    crack location = rcl2 Relative first crack depth = rcd1

    Relative second crack depth = rcd2

    A. Neural controller mechanism for crack detection

    The neural network used is a ten-layered perceptron. The

    chosen numbers of layers are found empirically to facilitate

    training. The input layer has six neurons, three for first three

    relative natural frequencies and other three for first three

    average relative mode shape difference. The output layer has

    four neurons, which represents relative crack locations and

    relative crack depths. The first hidden layer has 12 neurons,

    the second hidden layer has 36 neurons, the third hidden layer

    has 50 neurons, the fourth hidden layer has 150 neurons, the

    fifth hidden layer has 300 neurons, the sixth hidden layer has

    150 neurons, the seventh hidden layer has 50 neurons, and the

    eighth hidden layer has 8 neurons. These numbers of hidden

    neurons are also found empirically. Fig 5 depicts the neural

    network with its input and output signals.

    IV. EXPERIMENTAL INVESTIGATION

    To validate the numerical analysis result, an experiment on composite beam has been performed shown in fig 6. A composite beam was clamped at a vibrating table. During the experiment the cracked and un-cracked beams have been vibrated at their 1

    st, 2

    nd and 3

    rd mode of vibration by using an

    exciter and a function generator. The vibrations characteristics such as natural frequencies and mode shape of the beams correspond to 1

    st, 2

    nd and 3

    rd mode of vibration have been

    recorded by placing the accelerometer along the length of the beams and displayed on the vibration indicator. The experimental results are in close justification with neural analysis results. These results for first three modes are plotted in fig7. Corresponding numerical results for the cracked and un-cracked beam are also presented in the same graph for comparison. The comparison of results between neural controller, numerical, experimental analysis shown in table1.

    Fig.4 Neural model

    Fig. 5 Multilayers feed forward back propagation neural model for

    damage detection

    1. Data acquisition (Accelerometer); 2. Vibration analyser;

    3. Vibration indicator embedded with software (Pulse Labshop);

    4. Power Distribution; 5. Function generator; 6. Power amplifier;

    7. Vibration exciter; 8. Cracked Cantilever Composite beam

    Fig.6 Schematic block diagram of experimental set-up

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  • V. CONCLUSION

    The conclusions derived from the various analyses as

    mentioned above are depicted below.

    1. The Numerical analysis results are well agreed with

    neural analysis results.

    2. The investigation of vibration signatures of the

    cracked and un-cracked composite beam shows a

    variation of mode shapes and natural frequencies.

    3. The numerical analysis and neural analysis results are

    compared with the experimental results. They have

    good judgment.

    4. The present method can be engaged as a health

    diagnostic tool for vibrating faulty structures.

    5. Proposed health monitoring technique can be used for

    composite as well as isotropic material.

    VI. REFERENCES

    [1] A. Katunin, Identification of multiple cracks in composite beams

    using discrete wavelet transforms, Scientific Problems of

    Machines Operation and Maintenance, vol. 2(162), pp. 41-52,

    2010.

    [2] M. Krawczuk, and W. M Ostachowicz, Modelling and vibration

    analysis of a cantilever composite beam with a transverse open

    crack, Journal of Sound and Vibration, vol. 183(1), pp. 69-

    89,2005.

    [3] E.V.V. Ramanamurthy, and K. Chandrasekaran, Vibration

    analysis on a composite beam to identify damage and damage

    Severity using finite element method, International Journal of

    Engineering Scie and Techno, vol. 3, pp. 5865-5888, 2012.

    [4] P. M. Pawar and R. Ganguli, Matrix Crack Detection in Thin-

    walled Composite Beam using Genetic Fuzzy System, Journal of

    Intelli Material Sys and Struct, vol. 16(5), pp. 395 -409, 2005.

    [5] Rao, D.Srinivasa. Rao, K. Mallikarjuna, G.V. Raju, Crack

    Identification on a beam by Vibration Measurement and Wavelet

    Analysis, International Journal of Engineering Science and

    Technology vol. 2(5), pp.907-912, 2010.

    [6] M. Kisa, Free vibration analysis of a cantilever composite beam

    with multiple cracks, Composites Science and Technology, vol.

    64(9), pp. 1391-1402, 2004.

    [7] N. Hu, X. Wang, H. Fukunaga, Z.H Yao, H.X. Zhang, Z.S.Wu,

    Damage Assessment of structures using modal test data,

    International Journal of solids and structures, vol. 38(18), pp.

    3111-3126, 2001.

    Fig.7a. Relative Amplitude vs. Relative crack location from

    fixed end (1st mode of vibration)

    Fig.7b. Relative Amplitude vs. Relative crack location from

    fixed end (2nd mode of vibration)

    Fig.7c. Relative Amplitude vs. Relative crack location from

    fixed end (3rd mode of vibration)

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    sn

    f

    0.9

    979

    0.9

    989

    0.9

    944

    0.9

    989

    0.9

    986

    0.9

    973

    0.9

    857

    0.9

    985

    Rel

    ativ

    e

    firs

    t

    nat

    ura

    l

    freq

    uen

    cy

    fn

    f

    0.9

    987

    0.9

    997

    0.9

    958

    0.9

    981

    0.9

    981

    0.9

    989

    0.9

    980

    0.9

    993

    Tab

    le1

    . C

    om

    par

    ison

    of

    resu

    lts

    bet

    wee

    n N

    eura

    l co

    ntr

    oll

    er, nu

    mer

    ical

    and

    exp

    erim

    enta

    l an

    aly

    sis

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  • Dynamic response of a simply supported beam with

    traversing mass Shakti.P.Jena

    Mechanical Engineering Department

    National Institute of Technology

    Rourkela, Odisha, India

    [email protected]

    Dayal R.Parhi Mechanical Engineering Department

    National Institute of Technology

    Rourkela, Odisha, India

    [email protected]

    Abstract- In the present research, A theoretical- computational

    technique has been developed to evaluate the dynamic response of a

    simply supported beam subjected to a traversing mass with different

    boundary conditions. The effects of speed of the moving mass on the

    dynamic response of the beam have been investigated and the critical

    influential speed (CIS) of the beam also found out. The governing

    equation of motion of the structures has been converted into a series

    of coupled ordinary differential equation and solved by fourth order

    Runge-Kutta technique.

    Keywords- Traversing mass, dynamic response, CIS, Runge-

    Kutta Technique

    Introduction : A traversing mass produces larger beam

    deflections and stresses than that of the same mass applied

    statically. Hence the analysis of structures subjected to

    traversing mass is of important problem. These deflections and

    stresses are the function of both velocity and time of the

    moving mass.The dynamic analysis of structures under

    moving loads has been an interesting subject of various

    researches over the last decades.Its mainly due to

    improvement of new high-speed vehicles and general drive to

    improve the active communications.

    Jeffcott [1] has first developed a technique to get the

    inexact solution for the problem of vibration with the action of

    moving and variable loads. Stanisic et al. [2] developed a

    theory to calculate the response of a plate to a multi-masses

    moving structure by Fourier transformation technique. The

    analysis shows that for the same natural frequency of the plate,

    the resonance is reached prior by considering the moving

    multi-masses system than by moving multi-forces system.

    Stanisic and Hardin [3] have examined to find out the response

    of a simple supported beam subjected to random no of moving

    masses by Fourier technique in the existence of external load.

    Stansic and Euler [4] have investigated an article to describe

    the dynamic response of the structures with moving masses

    using operational calculus method. Akin and Mofid [5] have

    developed an analytical-numerical method to compute the

    dynamic response of beams subjected to moving mass with

    arbitrary boundary states by variable separable technique and

    compared the results to finite element analysis (FEA). Olsson

    [6] has investigated the dynamic response of a simply

    supported beam with a continuous traversing load at constant

    velocity. Parhi and Behera [7] have investigated the dynamic

    deflection of a cracked beam with moving mass by Runge-

    Kutta technique and the energy method.

    Ichikawa et al. [8] have investigated the response of a multi

    span Euler-Bernoulli beam carrying moving mass by using

    Eigen function technique and direct integration method

    combinedlly. Siddiqui et al. [9] have analyzed the dynamic

    characteristics of a flexible cantilever beam with moving mass-

    sprung system by using perturbation, time-frequency and

    numerical methods. Azam et al. [10] have investigated the

    response of a Timoshenko beam under moving mass and

    moving sprung structures. Bilello et al. [11] have developed a

    scale-model experiment to analyze the response of a mass

    traversing on a Euler-Bernoulli beam by the application of

    theory of structural models. Lee and Renshaw [12] have

    investigated a new solution method to solve the moving mass

    structures problem for non conservative, linear, distributed

    parameter systems using complex Eigen function expansions.

    Sniady [13] has studied the dynamic response of a simple

    supported Timoshenko beam acted upon by a force traversing

    with constant speed. Esmailzadeh and Ghorashi [14] have

    studied the reaction of a Timoshenko beam subjected to a

    constant partly disseminated travelling mass. Dehestani et al.

    [15] have analyzed the necessity of Coriolis acceleration

    associated with the moving mass during the motion along the

    vibrating beam and the response of Timoshenko beam along

    with moving mass by introducing the coefficient of influential

    speed.

    In the present paper, the dynamic deflection of a simple

    supported beam with moving mass has been determined and

    the consequences of speed on the beams response also found out. The analysis has been carried out with constant mass

    magnitude at different velocities.

    Problem Formulation:

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  • Timet in Sec (Hinged-Hinged Beam)

    Dif

    lecti

    on

    at

    the m

    idsp

    an

    (mm

    )

    Considering a simply supported beam subjected to a moving

    mass M with velocity V. It is assumed that during the

    course of motion there is no separation between the moving

    mass and the beam .So the transverse of the moving mass with

    respect to the beam is ignored here.

    Nomenclature:

    L=Beam Length, m=Beam mass per unit length, M=Mass of

    the moving object, V (t) =Velocity of the moving mass with

    respect to time, I=Constant moment of inertia, =Distance travelled by the traversing mass from the fixed end.

    y(x,t)=Deflection of the beam at point of consideration with

    respect to time. ( )nT t Function of time. ( )n x Eigen

    functions of the beam (without M) with the same boundary conditions. n= Number of modes of vibration.

    Theoretical Study: Considering constant moment of inertia and neglecting the

    damping effect, the principal equation of motion of the beam

    with moving mass using Euler Bernoullis is given by

    (1)

    Where = Dirac delta function

    Considering the solution of eqn in series form and by variable

    separation method, the eqn (1) can be rewritten as

    (2)

    ( )nT t Function of of time or amplitude function to be calculated.

    They may be again written as in the form of

    4( ) ( ) 0iv x x (3)

    Where

    The R.H.S of equation (1) can be written in a series form :

    (4)

    Putting the values of eqn (2) in eqn (4), arranging the

    eqn (4) we can write:

    (5)

    Multiplying both sides of eqn. (5) p(x) and integrating over

    Entire beam length

    (6)

    By using the properties of Dirac Delta function and principle

    of orthogonality of p(x)

    (7)

    (8)

    Substituting the values of eqn. (7) and (5) in eq

    n. (1),To get the

    values of ( )nT t

    (9)

    Now applying equation (3) in equation (9);

    (10)

    Now the above equation may be reduced to :

    (11)

    The equation (11) must satisfy for every values of x and it is

    solved by 4th

    order Runge-Kutta Method.

    Numerical Study: For the numerical analysis the dynamic analysis of the simply supported beam has been carried out

    and the CIS value of the corresponding beam with moving

    mass has been found out.

    Beam Type- Mild Steel, Beam size = (80.350.02) m, n=3

    Moving mass= 480 kg.

    4 2 2 2 22

    4 2 2 2[ 2 ] ( )

    y y y y yEI m M g V V x

    t xx t x t

    0

    ( ) ( ) ( ) , 0

    L

    f x x dx f L

    0

    ( ) ( ) 0 , 0

    L

    f x x dx

    1

    ( , ) ( ) ( )n nn

    y x t x T t

    42 n

    n

    EI

    m

    2 2 22

    2 21

    [ 2 ] ( ) ( )n nn

    y y yM g V V x x S

    t xx t

    2 // /,

    1 1

    ,

    1

    1 0

    [ ( ) ( ) 2 ( ) ( )

    ( ) ( )] ( ) ( )

    ( ) ( )

    n n n n tL

    n n

    o

    n n tt p

    n

    L

    n n p

    n

    M g V x T t V x T t

    dx

    x T t x x

    S t x

    2 // /p ,

    1 1

    ,

    1

    S ( ) [ ( ) ( ) 2 ( ) ( )

    ( ) ( )] ( )

    n n n n tp n n

    n n tt p

    n

    Mt g V T t V T t

    V

    T t

    0

    ( ) ( )

    0,

    Lp

    n p

    V n px x dx

    n p

    , ,

    1 1

    ( ) ( )

    1

    ( ) ( ) ( ) ( ),1 1

    2( ) [

    12 ( ) ( ) ( ) ( )] ( )q q t q q tt n

    q q

    q T tqq

    ivEI x T t m x T tn n n n tt

    n n

    Mx g Vn

    Vn

    nV T t T t

    4 2 //,

    1

    /, ,

    1 1

    ( ) ( ) [ ( ) ( )

    2 ( ) ( ) ( ) ( )] ( ) 0

    n n n tt q qn q

    q q t q q tt n

    q q

    MEI T t mT t g V T t

    V

    V T t T t

    4( ) ( ),

    2 // /( ) [ ( ) ( ) 2 ( ) ( ) 0,

    1 1 1

    ( ) ( )] ( ),1

    MEI T t mT tn n n tt

    Vn

    x g V T t V T tn q q q q tn q q

    T tq q tt nq

    2 // /, ,

    1 1 1

    1

    [ ( ) ( ) 2 ( ) ( ) ( )] ( )

    ( ) ( )

    n n n n t n n tt

    n n n

    n n

    n

    M g V x T t V x T x T t x

    x S t

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  • Results and Discussion: The CIS may be analysed as the velocity of the traversing mass at which the structure produces

    maximum deflection with time variation. The dynamic

    response of the simply supported structures of hinged-hinged

    & fixed-fixed type with various velocities have been examined

    and the deflection at the mid span of the beam also calculated.

    It has been observed that for the hinged-hinged type beam

    115m/s and for the fixed-fixed type simply supported beam

    215m/s is the critical influential speed of the beam. It has been

    observed that if we are increasing the speed of the moving

    mass beyond the CIS value, the beam deflection will start

    decreasing. The consequence of critical speed and the inertia

    pertaining to the traversing mass has also been studied. The

    displacement of the traversing mass and the structure under

    the location of the moving object are calculated in terms of

    timet.

    Conclusion: The dynamic response of simply supported beam with various velocities at different boundary conditions

    has been investigated theoretically and computationally. The

    CIS value of the corresponding beam also calculated from the

    beam deflection. The deflection of the beam mainly depends

    upon the velocities of the moving object.

    References:

    1. Jeffcott.H ; On the vibration of beams under the action of moving loads,

    Philosophical magazine series7. 1929, Vol.8 (48),pp.66-97.

    2. M. M. Stanisic, Baltimore, Md., J. C. Itardin and Y. C. Lou, Lafayette, Ind. On the response of the plate to a multi-masses moving system, Acta

    Mechanica, 1968,vol.5,pp.37-53.

    3.M.M Stanisic and Hardin.J.C,On the response of beams to an atbitry number of moving masses, J.Franklin Institute,1969,Vol.187(2),pp.115-123.

    4. M.M.Stanisic,On the dynamic behavior of the structures carrying moving

    masses,Ingenieur-Archiv of Applied Mechanics,1985,Vol.55(3),pp.176-185. 5. John E.Akin and Massood Mofid,Numerical solution for the response of

    beams with moving mass, Journal of Structural Engg,1889,

    Vol.115(1),pp.120-132.

    6. M.Olsson, On The Fundamental Moving Load Problem, Journal of sound and vibration, 1991, Vol. 145(2), pp.299-307

    7. D.R Parhi and A.K.Behera , Dynamic deflection of a cracked beam with

    moving masses, Journal of mechanical engineering science,1997,Vol.211,pp.77-87.

    8. M. Ichikawa, Y.Miyakawa and A. Mastuda , Vibration analysis of a

    continuous beam subjected to a moving mass, Journal of Sound and Vibration, 2000,Vol.203(4),pp..493-506.

    9. S.A.Q. Siddiqui, M. F . Golnaraghi and G.R.Heppler , Dynamics of a

    flexible beam carrying a moving mass using perturbation ,numerical ,time-frequency analysis technique, Journal of Sound and Vibration,

    2000,Vol.229(5),pp.1023-1055.

    10. S. Eftekhar Azam , M. Mofid and R. Afghani Khoraskani , Dynamic

    response of Timoshenko beam under moving mass , Scientia Iranica , 2013,

    Vol. 20 (1), pp.5056.

    11.Cristiano Bilello, Lawrence A. Bergman and Daniel Kuchma ,

    Experimental Investigation of a Small-Scale BridgeModel under a Moving

    Mass , Journal of Structural Engineering ,2004, Vol.130(5),pp.799-804.

    12. K.Y. Lee and A. A. Renshaw , Solution of the Moving Mass Problem

    Using Complex Eigen function Expansions ,Journal of Applied

    Mechanics,2000,Vol.67, pp.823-827.

    13. Pawel Sniady , Dynamic Response of a Timoshenko Beam to a Moving Force , Journal of Applied Mechanics, 2008, Vol.75, pp.24503(1-4).

    14. E. Esmailzadeh and M . Ghorashi , Vibration analysis of a Timoshenko

    beam subjected to a Travelling mass, Journal of Sound and Vibration,1996, Vol.199(4),pp. 615-628.

    15. M. Dehestani, M. Mod and A. Vafai , Investigation of critical inuential speed for moving mass problems On beams, Journal of Applied Mathematical Modelling,2009, Vol.33,pp-

    3885-3895.

    16. L.Fryba, Vibration of solids and structures (1999), Third Edition, Thomas Telford Ltd , Prague

    17. W.T.Thomson, Theory of Vibration with Application (2002) Third

    Edition.CBS Publishers , New Delhi.

    Timet in Sec(Fixed-Fixed Beam)

    Defl

    ecti

    on

    at

    mid

    spa

    n (

    mm

    )

    Def

    lect

    ion

    at

    mid

    spa

    n (

    mm

    )

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  • [1]

    Mathematical modelling of steady state temperature distribution due to heat loss

    from weld bead of a butt joint Jaideep Dutta, Postgraduate Research Scholar

    Department of Mechanical Engineering National Institute of Technology Karnataka,

    Surathkal Mangalore, India

    Email-id: [email protected]

    AbstractIn this paper a steady state non-linear analytical thermal analysis has been carried out to determine the temperature distribution due to heat loss from weld bead formed in a butt weld joint. The perturbation method has been incorporated to judge the nature of temperature distribution from the weld pool towards the longitudinal direction of the rectangular plate. The analysis has introduced non-dimensional variable in conjunction with variable thermal conductivity. For two different materials, stainless steel of grade AISI 316 and low carbon steel of grade AISI 1005, the temperature distribution phenomena has been observed. The analysis reveals that the non-dimensional parameter of temperature derived from analytical model has shown good agreement with the established model of moving point heat source and this entails that temperature cycle of weld bead due to heat loss by conduction, is in decreasing mode towards the longitudinal direction of the welded plate.

    Keywords Perturbation technique, temperature cycle, moving point heat source, non-dimensional parameter.

    Nomenclature

    Asymptotic function

    K Thermal conductivity

    T Temperature

    Perturbation parameter

    x Space variable

    Thermal expansion coefficient (/C)

    Non-dimensional temperature distribution term

    X Non-dimensional length

    L Length of the weld plate

    Specific Heat (J/kg-K)

    Net heat input (J/m)

    Narendranath S., Professor

    Department of Mechanical Engineering National Institute of Technology Karnataka,

    Surathkal Mangalore, India

    Email-id: [email protected]

    Density (kg/m3)

    Welding velocity (m/s)

    y Particular location from fusion boundary (m)

    t Thickness of base metal (m)

    Subscripts

    0, 1, 2. 0th order, 1st order, 2nd order respectively.

    i initial

    o Final

    p Peak temperature

    m Melting point

    I. INTRODUCTION

    Fusion welding of metals is a process which comprises heating and cooling cycle. The thermal analysis of fusion welding covers numerous aspects such as the physics and behavior of arc with the formation of weld pool, development of residual stress and distortion in weldments, characterization of heat affected zone (HAZ), metallurgical properties of joints. All these properties are integrated to improve the weld structures in structural applications. Quantification thermal aspect shows immense importance as the source of all the changes such as chemicalmetallurgical phenomena in liquid solid interface of weld pool, liquid-solid phase transformation and variation of relevant mechanical properties, are solely dependent of temperature gradients induced due to appearance of successive thermal cycles [1, 2]. Most prominent analytical model to predict the heat transfer characteristics is Rosenthals model [3] and still it is one of the basic simple model for

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  • [2]

    illustration. Pavelic et al. [4] first proposed the heat source as Gaussian distribution on the surface of the welded plate. Dimensional parameters were first introduced by Tsai N. S. and Eagar [5]. After this appreciable work has been done by Goldak et al. [6] assuming pseudo-Gaussian heat source. Some recent notable works done by researchers such as Hou Z. B. and Komanduri R. [7] analytically derived general solutions of moving point heat source in both transient and stationary state; Araya Guillermo and Gutierrez Gustavo [8] obtained analytical solution for a transient, three dimensional temperature distribution due to a moving laser beam; Elsen Van M. et al. [9] presented the analytical and numerical solution for modelling of localized moving heat sources in a semi-infinite medium and illustrated its application to laser processing materials; Kukla-kidawa J. [10] explored the exact solution of temperature distribution in a rectangular plated heated by a moving heat source obtained by Greens function method; Levin Pavel [11] developed a general solution of three dimensional quasi-steady state problem of moving point heat source on a semi-infinite solid; Osman Talaat and Boucheffa Abderrahmane [12] proposed an analytical model based on integral transform and finite cosine Fourier integral transform to compute 3-D temperature distribution in a solid by moving rectangular with surface cooling; Winczek Jerzy [13] suggested an analytical model of computation of transient temperature field in a half infinite body caused by moving volumetric heat source with changeable direction of motion; Parkitny Ryszard and Winczek Jerzy [14] described analytically the solution of temporary temperature field in half infinite body caused by assuming moving tilted volumetric heat source with Gaussian power density distribution with respect to depth. Motivated by these facts the present analysis has been carried out in order to estimate the non-dimensional temperature distribution from weld bead of square butt joint to the longitudinal direction by non-linear steady state analysis. By assuming variable thermal conductivity, the perturbation technique (asymptotic) has been adopted as it allows to evaluate the approximate solutions which cant be determined by traditional analytical method. For different temperatures starting from melting point of the metal i.e. liquid weld pool, the analysis has been illustrated the temperature cycle as the distance increasing towards the rear end of the weld plate.

    II. BASIC IDEA OF PERTURBATION

    METHOD

    Perturbation method, also known as asymptotic method is a simplification of complex mathematical problems [15]. It is very difficult to solve higher order non-linear differential equations analytically

    whereas this method is acceptable in this situations. Though numerical methods are very popular for solving mathematical problems but they consist of error. Perturbation method can be an alternative approach for solving equations with comparatively higher accuracy. The first step of implementation of this theory is to nondimensionalize the governing equation. Then it requires a small parameter with very small magnitude which appears as dimensionless form in the equation. This parameter usually denoted as , is in the range of0 1. Then the non-dimensionalized equation needs to be expanded in an asymptotic nature with the form [16]:

    = + + + (1)

    Then the assumed equation is substituted into governing equations and equating the terms of identical powers of , gives the formulation of nth order formulation.

    III. MATHEMATICAL FORMULATION

    In order to implement the perturbation method the basic assumptions of this modelling are: (a) 1-D heat conduction, (b) Temperature dependent thermal conductivity, (c) Steady state heat transfer, (d) No energy generation, (e) Other modes of heat transfer (convection and radiation) have been neglected and (f) No phase change. Based on above assumptions, the heat transfer equation on the domain (Fig. 1) is [17]:

    K(T)

    = 0 (2)

    K(T) = K[1 + (T T)] (3)

    The boundary conditions are:

    T(x = 0) = T (4) T(x = L) = T (5) To identify an appropriate perturbation parameter the following nondimensional variables are used:

    =T TT T

    , X =x

    L

    Substituting the nondimensional variables in (2)

    {1 + (T T)}

    = 0 (6)

    Thus the perturbation parameter can be expressed as:

    = (T T) (7) Thus (6) becomes,

    (1 + )

    = 0 (8)

    Now as (8) is nonlinear, the boundary equations (4) and (5) becomes:

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  • [3]

    Fig. 1. Schematic diagram of square butt joint of two rectangular plates indicating the domain of heat conduction

    (x = 0) = 1 (9) (x = L) = 0 (10)

    Now using (1) asymptotic equation as mentioned, (8) results:

    {1 + ( + +

    + )}

    ( + +

    + ) = 0 (11)

    After differentiating and expanding, (11) becomes:

    +

    +

    +

    + [

    ] +

    + 2

    +

    = 0 (12)

    Now equating the identical powers of , yields:

    :

    = 0 (12.a)

    :

    +

    + [

    ] = 0 (12.b)

    :

    +

    + 2

    +

    = 0

    (12.c) Applying boundary condition (9) into (1), (0) + (0) +

    (0) + = 1 (13) Equating identical powers of : (0) = 1, (0) = 0and(0) = 0 Proceeding same way, applying boundary condition (10), into (1): (1) + (1) +

    (1) + = 0 (14) Again equating identical powers of :

    (1) = 0, (1) = 0and(1) = 0 The solution has been derived as follows: (a) 0th order solution: Applying boundary conditions (0) = 1 and (1) = 0 in 12.a,

    ddX

    = 0

    Thus, = 1 X (15) (b) 1st order solution: Substituting as expressed in (15), into 12.b and applying boundary conditions (0) = 0and (1) = 0 gives,

    ddX

    = 1

    Thus, =

    (1 X) (16)

    (c) 2nd order solution: Substituting and from (15) and (16) into 12.c and applying boundary conditions (0) = 0 and (1) = 0 yields:

    ddX

    = 2 3X

    Thus, =

    (2X X 1) (17)

    Finally substituting, and into (1) results:

    = (1 X) +

    (1 X) +

    (2X X 1) +

    (18)

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  • [4]

    IV. EMPIRICAL MODEL FOR PEAK TEMPERATURE DISTRIBUTION

    According to Masubuchi [20], the temperature distribution peak in welded zones, specifically in the Heat Affected Zone (HAZ) and its vicinity can be determined by using (19)

    ()=

    .

    +

    () (19)

    IV. RESULTS AND DISCUSSION

    TABLE I. THERMOPHYSICAL PROPERTIES OF MATERIALS [18, 20]

    Material Stainless steel (AISI 316)

    Low carbon steel (AISI 1050 )

    Melting point (C)

    1510 1425

    Thermal expansion coefficient (/C)

    15.9 10 11.7 10

    Density (kg/m3) 8000 7872

    Specific heat (J/kg-K)

    500 481

    0.00 0.15 0.30 0.45 0.60 0.750.00

    0.15

    0.30

    0.45

    0.60

    0.75

    0.90

    1.05

    1.20

    No

    n-d

    ime

    ns

    ion

    al

    tem

    pe

    ratu

    re d

    istr

    i